Determination of Palladium in Alloy by Flame Atomic Absorption Spectrometry after Preconcentration of Its Iodide Complex on Amberlite XAD-16

Abstract

Palladium is one of the precious metals. In the field of analytical science, palladium is used as a matrix modifier for the determination of several metals by electrothermal atomic absorption spectrometry. 1,2 Owing to its corrosion resistance nature and alloying ability, palladium is an important element in metallurgy. Its alloys are used in dental and medicinal devices and in jewelry manifacture. Moreover, palladium is used in automobile catalysts together with Pt and Rh. They oxide specific toxic components such as carbon monoxide, hydrocarbons and also various nitrous oxides in hot gases as they pass through the exhaust system. 3,4 Palladium can be determined by expensive instruments such as inductively coupled plasma atomic emission spectrometer, 3,5,6 glow discharge mass spectrometer 4 and electrothermal atomic absorption spectrometer 1,2,7 either with or without separation and preconcentration steps.Palladium is widely determined spectrophotometrically after preconcentration by extraction, adsorption or reversed phase high-performance liquid chromatography. [8][9][10][11][12][13][14][15][16][17][18][19][20] Spectrophotometric determination is normally simple, but solvent extraction of palladium is difficult because of slow extraction rates. Because the complexing of palladium is difficult at room temperature, heating the solution or using a catalyst can be necessary. In addition, any excess of reagent is also extracted into the organic phase causing high reagent blanks. For such reasons, many improvement studies have been done and many complexing agents have been tested for increasing the extractibility of palladium. [9][10][11][12] Flame atomic absorption spectrometry (FAAS) is a simple and cheap technique for the determination of trace amounts of palladium. But, because of the low abundance of palladium in many samples, the direct determination of it by FAAS is often difficult. Moreover, with the air-acetylene system, severe depression of absorbance occurs in the presence of iridium and nickel and smaller but noticeable depression in the presence of iron, chromium and platinium. 21 In order to prevent these interferences and increase sensitivity, generally separation and preconcentration of palladium from sample matrix are necessary. For this purpose, extraction, 22 ion exchange 23 or adsorption 24 techniques have been used.In this study, adsorption has been used as an enrichment technique.Because of the purity and good adsorption properties, Amberlite XAD-16 resin, which has the largest surface area of Amberlite XAD series, was used as adsorbent. The various parameters such as pH, elution solution, volume of sample, complexing agent, interfering ions and flow rate have been evaluated. The procedure developed has been succesfully employed for the trace determination of palladium in alloys. Experimental ApparatusA Philips PU 9285 flame atomic absorption spectrometer was used for the determination of palladium; it was equipped with a deuterium lamp background correction, a hollow cathode lamp and an air-a...

Solid Phase Selective and Extractive Preconcentration of Silver Ion from Aqueous Samples on Modified Silica Gel with 5-(4-Dimethylaminobenzylidene)-Rhodanine; Prepared by Sol-Gel Method

“…Accordingly, several selective solid phase extractors have been prepared by either physical loading or chemical binding of selected chelating reagents to silica gel for preconcentration of silver ion. [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] In this study, an easy and efficient method for the preparation of a modified silica gel sorbent for preconcentration of Ag + ion is introduced. A two-step sol-gel method 28 has been applied for the modification of silica gel and immobilizing of 5-(4-dimethylaminobenzylidene)-rhodanine (DBR) (Fig.…”

Estimation of platinum in environmental water samples with solid phase extraction technique using inductively coupled plasma mass spectrometry

“…Solid phase extraction has been demonstrated to be a highly effective preconcentration method when first applied to spectrometric determination [14,19,20]. Among the different sorbents that were tested for this enrichment stage are resins such as polyacrylacylaminothiourea [21], imidazoline [22], Metalfix-Chelamine [23,24], Amberlite XAD-16 [25], Amberlite XAD-7 [26], Dowex 1-X10 [27], Polyorgs 17 [28], HHY-10A macropore anion resin [29], activated alumina [30] and modified silica gels like silica gel functionalized with 1,5-bis(di-2-pyridyl)methylene thiocarbohydrazide [31], modified silicagel SeparonTM SGX [32], silica gel modified with propylamine groups [33]. Very good sorption properties of this last resin led us to choose it for the present study.…”

Speciation and Determination of Heavy Metals in Lake Waters by Atomic Absorption Spectrometry after Sorption on Amberlite XAD-16 Resin

“…Among these techniques used in trace element determination, adsorption is one of the most widely used. For this purpose, commercially available Amberlite XAD copolymers [13][14][15][16] have been widely used as adsorbents suitable for multielement preconcentration from different matrices, because of their purity and good adsorption properties. Amberlite XAD-16 resin is an adsorbent based on polystyrene divinylbenzene-copolymer.…”